Many different toys are known in the art and used by children for amusing and educational purposes. One of the main purposes of giving a toy to a child is to generate attachment between the child and the toy. The closer the relationship between the child and the toy, the higher will be educational and humane value of the toy. This is especially, but not exclusively, true with respect to the toys formed as dolls. In dolls, it is very important if a doll imitates a real human being by producing certain visual or sound features resembling those of human beings or animals, by reacting to environmental factors or irritants similarly to human reactions. It is also important if a doll reacts to rocking similarly to a child which is rocked to sleep. Another advantage is the ability to play doctor by applying a toy stethoscope to a doll, which however in conventional toys is very limited.